Electric signaling



a @9 31 WUR 1,834,408

ELECTRIC SIGNALING Filed March 9, 1925 m INVENTOR iii;

Patented Dec. 1, 1931 UNITED STATES PATENT; OFFICE MABIUS LATOUB, OF NEW YORK, N. Y ASSIGNOB TO LATOUR CORPORATION, OF JERSEY CITY, NEW JERSEY, A; CORPORATION OF DELAWARE ELECTRIC SIGN ARIN G Application filed. Karel; 9, 1925. Serial No. 14,221.

One of the principal objects of my invention is the provision of simple and efl'ective means for preventing the establishment of undesirable oscillations in signaling systems.

Another object of my invention is the provision of simple, cheap and effective coupling means between various devices in Sig-.

naling systems, said couplin means also improving the degree and quahty of amplifica- 1 tion.

. companying drawin Other objectsand advantages of my invention will be apparent from the following description taken in conjunction with the ac- Beferrmg to the rawing which is a schematic diagram of a preferred embodiment of my invention, the control-electrode cathode circuit of thermionic tube or relay 1 is coupled to the source of signal waves bymeans of the coupling device 2. The coupling device 2 comprises a rimary and a secondary coil inductively related to each other as shown. The primary coil is connected across the source of signal waves and has a variable condenser 3 connected. across its terminals for tuning to the desired frequency.

The control electrode-cathode circuit of relay 1 comprises an inductance 4. and the sec-- ondary winding of coupling device 2 connected in series with each other and arranged in the circuit as shown. A condenser 5 is connected across the secondary winding for tuning the circuit to the desired frequency. The inductance 4 preferably possesses a magnetic circuit comprising magnetic material whereby the im edance of the inductance increases material y as the si al frequency in-. creases. This is desirable 1n view of the fact that the higher the fr uency the greater the tendency is to the esta lishment of undesirable oscillations,and therefore the desirability of a greater im edance in the grid circuit for preventing t e establishment of these oscillations.

' The anode-cathode circuit of relay 1 com-' prises the primary winding 7 of transformer" 6 and the source of space current B connected in series and arranged in the circuit as shown. The magnetic circuit of transformer 6 preferably comprises magnetic material al- The control electrode cathode circuit of relay 8 comprises the secondary winding 9 of transformer 6 and inductance device 10 connected in series with each other and arranged in the circuit as shown. The inductance 10 is preferably of the air core type and serves to neutralize the capacity effects of the relay 8 to thereby prevent the establishment of undesirable oscillations.

A condenser 11 may be connected across the winding 9 for tuning the control electrodecathode circuit to the desired frequency. A variable condenser 12 is connected between points on the windings 7 and 9. The degree of amplification together with the quality of amplification is found to be greatly improved by this arrangement.

The anode-cathode circuit of relay 8 com prises the primary winding 13 of transformer 14 and the source of space current B connected in series with each other and arranged in the circuit as shown. A variable condenser 15 may be connected in this circuit, as shown, for tuning it to the desired I frequency.

The control electrode-cathode circuit of relay 45 comprises an inductance 16 and the secondary winding 17 of transformer 14 connected in series with each other and arranged in the circuit as shown. A variable condenser 18 is connected in shunt with the inductance 16 for effecting an increase in the impedance of the combination with an increase in signal fr uency to thereby revent ment 0 undesirable oscil ations.

the establis A variable condenser 19 may be connectwindings 13 and 17 thereby resulting in a relay 24 comprises a resistance 25 and the secondary winding 26 of transformer 22 connected in series with each other and arran ed in the circuit as shown. A- shunt comprising an inductance'27 and a condenser 28 connected in series with each other is connected across points of said resistance, one of said points being variable, as shown. As the signal frequency increases this shunt forces more current through the resistance 25 and therebyincreases the resistance to the establishment of undesirable oscillations. A condenser 29 may be connected across the winding 26 for tuning the circuit to the desired frequency. A condenser 30 is also referably connected across points on win ings 21 and 26 as shown. The anode-cathode circuit of relay 24 may be appropriately connected to some other device such as a detector, etc.

All of the variable tuning elements may be simultaneously controlled by a single control means or they may be controlled in vanous oups.

While I have shown and described a preferred embodimentof my invention, I do not limit myself to the same; but may employ such other modifications as come within the spirit and scope of my invention.

I claim:

1. In a wave signalin system, a vacuum tube having a grid, a plate and a filament, a tunable circuit comprising an inductance and a variable condenser in parallel, said filament being connected to one terminal of said condenser, a resistance connected between the other terminal of said condenser and said grid, said resistance being not included in said tunable circuit, and a shunt path across the terminals of said resistance, said shunt path comprising an inductance and a condenser in series.

2. In a signaling system, the combination with a thermionic tube including anode, cathode and grid, of input and output circuits associated with said cathode .and grid and said cathode and anode respectively, whereby there exists a tendency for the setting up of undesired oscillations in said tube, and means for preventing such undesired oscillations, comprising in series with said input circuit and said tube an inductance shunted by a capacity.

3. In a signaling system, the combination with a thermionic tube including anode, cathode and grid, of an input circuit con-' nected between said grid and cathode and an output circuit connected between said cathode and anode respectively, whereby there exists a tendency for the setting up of undesired oscillations in said tube, andmeans serially interposed between said input circuit and said grip for preventlng such oscillations, said means comprising an inductance shunted by 9. ca acity.

4. In a signa ing system, the combination with a thermionic tube including anode, cathode and grid, of input andoutput circuits associated with said cathode and grid, and said cathode and anode respectively, whereby there exists a tendency, increasing with frequency, for the settin up of undesired oscillations in the said tu and means in series with said input circuit for preventing such oscillations, comprising inductive reactance shunted by an impedance such that the resultant impedance of said means increases with frequency at a rate sufiicient to offset the increased tendency at the higher frequencies for the setting up of such oscillations.

5. In a signaling system, the combination with a thermionic tube including anode, cathode and grid, of input and output circuits associated with said cathode and grid and said cathode and anode 1 respectively, whereby there exists a tendency, increasing with frequency, for the settin up, of undesired oscillations in the said tu e and means in series with said input circuit for preventing such oscillations, comprising an inductance shunted by a ca acity such that the resultant impedance 0 said means increases with frequency at a rate suflicient to offset the increased tendency at the higher frequencies for the setting up of such undesired oscillations.

6. In a signalin system, a thermionic tube provided with a fi ament, a grid and a plate, an input circuit for said thermionic tube including the secondary winding of a transformer havin a ca acity connected in multiple therewit said input circuit including said grid and said filament, an inductance unit in series with said input circuit and an impedance unit in shunt with said inductance unit whereby the impedance of said input circuit increases with frequency in order to prevent oscillations, and an output circuit for said thermionic tube including said filament and said plate.

7. In a signaling system, a thermionic tube provided with a filament, a grid and a plate, an input circuit for said thermionic tube including the secondary winding of a transformer and a capacity connected in multiple,

' mionic tube.

8. In a signaling system, the combinationwith a thermionlc tube including anode, cathode and grid, of input and output circuits associated with said cathode and grid and said cathode and anode respectively, whereby there exists a tendency, increasing with fre uency, for the setting up of undesired oscillations in said tube, and means for preventing such oscillations comprising a resistance in series with said input circuit and said tube, and an impedance including inductance connected in shunt withsaid resistance, said resistance and impedance being so pro ortioned that the resultant impedance of em rate suflicient to offset the increased tendency at the higher frequenciesfor the setting up of such undesired oscillations.

9. In a signaling system, the combination with a thermionic tube including anode, cathode and grid, of input and output circuits associated with said cathode and grid and said cathode and anode respectively, whereby there exists a tendency, increasing with fre uency, for the setting up of undesired osci lations in said tube, and means for preventin resistance in series with said input circuit and said tube, and an impedance includin in ductance and capacity connected in s unt with said resistance, said resistance and impedance being so proportioned that the resultant impedance of said means increases with frequency at a rate sufiicient to offset the increased tendency at the higher frequencies for the setting up of such undesired oscillations.

10. In a signaling system, the combination with a thermionic tube including anode, cathode and grid, of input and output circuits associated with said cathode and grid and said cathode and anode respectively, whereby there exists a tendency, increasing with fre uency, for the setting up of undesired oscillations in said tube, and means for preventing such oscillations, comprising a resistance in series with said input circuit and said tube, and animpedance in shunt with said resistance, said impedance includin capacity and inductance in series, and sai resistance and impedance being so proportioned that the resultant impedance of said means increases with frequency at a rate sufiicient to offset the increased tendency at the higher frequencies for the setting up of such undesired oscillations.

11. In a signaling system, the combination means increases with frequency at a such oscillations, comprising a;

with a thermionic tube having anode, cath-- ode and grid, of input and output circuits associated with said cathode and grid and said cathode and anode res ectively, whereby there exists a tendency or the setting up of undesired oscillations in'said tube, and

means for preventing such oscillations combeing connected to one terminal of said con-' denser, a resistance connected between the other terminal of said condenser and said grid, said resistance being not included in said tunable circuit, and an impedance variably shunting said resistance, said impedance comprising an inductance and a capacity in series.

13. In a signaling system, the combination with a thermionic tube including anode, cathode and grid, of an input circuit connected between said grid and cathode and an output circuit connected between said cathode and anode, respectively, whereby there exists a tendency for the setting up of undesired oscillations in said tube, and means serially interposed between said input circuit and said grid for preventing such oscillations, said means comprising a resistance variably shunted by inductance and ca acity in series.

14. In a signaling system, tlie combination with a thermionic tube including anode, cathode and rid, of input and output circuits associate; with said cathodeand grid and said cathode and anode, respectively, whereby there exists a tendency for the setting up of undesired oscillations in saidtube, and means in series with said input circuit and said tube for reventing such oscillations comprising resistance variably shunted by capacity and inductance in series such that the resultant impedance of said means increases with frequency at a rate sufiicient to offset the increased tendency for the setting up of such undesired oscillations at the hlgher frequencies.

15. In a radio frequency amplifying systern, the combination with a thermionic tube including anode, cathode and grid, of input and output circuits associated with said cathode and grid and said cathode and anode respectively, whereby there exists a, tendency, increasing with frequency, for the setting up of undesired oscillations in said tube, and means for preventing such oscillations, comprising a resistance in series with said input circuit, and animpedance. including capacity in shunt with said resistance, said resistance and impedance being so proportioned that the resultant impedance of said means 1ncreases with frequency at at rate sufiicient to ofiset the increased tendency at the higher frequencies for the setting up of such undesired oscillations. 5 16. A signal receivin system including a plurality of electron tu es each having grid, filament and plate electrodes, input and output circuits mterconnecting said electrodes with the output circuit of one electron tube interlinked With the input circuit of a sueceeding electron tube, and a pair of parallel branch circuits connected in the input circuit of one of said electron tubes, an inductance and capacity in series in one branch 15 thereof and resistance in the other branch thereof, said circuits having an effective resistance variable et e predetermined rate in proportion to the selected signelin fre uency for preventing the flow back of un esired z oscillatory currents while permitting the free transfer of signaling energv of a selected fre uency through said plurality of electron tu es. 17. A signal receiving system including a 25 plurality of electron tubes each having grid, filament and plate electrodes, input and out- 1 put circuits interconnecting seid electrodes with the output circuit of one electron tube interlinked with the input circuit of a suceo ceeding electron tube, and a pair of parallel branch circuits connected in the input circuits of seid electron tubes, said parallel branch circuits having an efiective resistance variable at e predetermined rate in accordee ence with changes in fre uency and operating to prevent the flow ack of undesired oscillatory current in said circuits While permitting the free transfer of signaling -energy of selected frequency cheracteristie MARIUS LATOUR. 

